Effects of a stylus on the surface roughness determination in a contact method for paper and paperboard

Abstract

Surface characterization is important and has many applications in the paper industry. It includes both surface roughness and surface friction. In determining the surface roughness of paper and paperboard, non-contact methods such as air-leak methods In characterizing the surface roughness of paper and paperboard, it has been a common practice that the average roughness with the coefficient of variation (COV) has been conventionally determined. This practice, however, this runs the risk of drawing wrong conclusions since two different surfaces having the same average roughness and COV can exhibit totally different properties. To avoid such mistake, a stylus-type contact method has been developed to determine surface roughness of paper and paperboard such as printing & writing (P&W), kraft and liners. In this method, surface roughness profile has been generated to determine its variability which has been defined as the mean deviation from the roughness average, referred to as MDRA. In determining the MDRA, it is noted that thickness measurement is not required. In this method, stylus shape and size, contact force of the stylus to the surface, scan speed and resolution have been identified as the key parameters of generating stable surface roughness profiles. It has been further identified that the optimal conditions on these parameters should depend on paper grade. It is suggested that a stylus-type contact method should be used to determine surface roughness of paper and paperboard to help determine their practical applications such as printing, coating and embossing.

Surface characterization of paper products via a stylus-type contact method

“…4 was unsuccessful for testing the samples except for R1 and R2 at the contact force of 3 gf or 5 gf. This result is similar to behavior of the truncated pyramid as reported by Jeong et al (2019). Meanwhile, the tip diameter of 1.0 mm (d2) was successful for testing all samples.…”

“…In determining the surface roughness of paper and paperboard, three types of the methods are currently available: non-contact type, indirect type, and contact type (Jeong et al 2019). Meanwhile, only a contact type may be used to determine surface friction.…”

Collaborative Optimization of Density and Surface Roughness of 316L Stainless Steel in Selective Laser Melting

“…Experimental samples with the size of 8 mm × 8 mm × 8 mm were fabricated on the base plate of this equipment and removed by wire cutting. Surface roughness was measured using a TR200 roughness meter with an accuracy of 0.001 µm (Beijing Jitai Scientific Instrument & Testing Equipment Co., Ltd., Beijing, China) using a contact measurement method [20]. First, the bottoms of samples were polished to a plane.…”

Collaborative Optimization on Density and Surface Roughness of 316L Stainless Steel in Selective Laser Melting

“…The employed SLM equipment in this study is an FS271M metal 3D printer (Hunan Farsoon High-Technology Co., Ltd, Hunan, China) and its corresponding specifications and parameters are shown in Table 1. The surface roughness (SR) was measured by TR200 roughness meter with an accuracy of 0.001μm (Beijing Jitai Scientific Instrument & Testing Equipment Co., Ltd) using a contact measurement method [18]. The relative density (RD) is expressed as the ratio between the measured density and the theoretical density.…”